Question: $\dfrac{9}{2} - \dfrac{7}{8} = {?}$
Explanation: $ = {\dfrac{9 \times 4}{2 \times 4}} - {\dfrac{7 \times 1}{8 \times 1}} $ $ = {\dfrac{36}{8}} - {\dfrac{7}{8}} $ $ = \dfrac{{36} - {7}}{8} $ $ = \dfrac{29}{8}$